How to drive a car on board a car-transporter at full speed
One of the simpler exercises in stunt driving is the trick of driving a car onto a moving target. It is quite important you know what you are doing, though, as there is a certain amount of danger involved.
For the purpose of this node, we will be driving a car with manual transmission (see how to use a manual transmission), as the intricacies of doing this in an automatic transmission car are lost on me - if it is even possible.
Where is it used?
First off, do your research. There is a famous example of this stunt in the Italian Job - the original one, with the minis that are actually small enough to deserve carrying the "mini" name. It may be in use in other movies as well, but this example stands out. If you know of any others - let me know!
Other shows it is used, apparently: knight rider
Basically, you want to drive one car onto the trailer or the transport-level of another car. In our case, drive a regular, small car onto a transporter of some description. To do this, the stunt driver will have to drive up a pair of ramps, onto / into the transporter.
The difficulty in this is obvious: You go from a state where the wheels turn very fast, into one where the front wheels stand still, but the rear wheels are still in motion, into one where all the wheels are stationary. This demands a particularly good aim, and excellent driving skills.
How to do it, then?
For the purpose of this writeup, let's assume we are using a front wheel drive car. This assumption is for two reasons: One, the minis have front wheel drive, and two, I have only ever tried this stunt in a front wheel drive vehicle (a mini, since you ask).
During practice, obviously it is useful if the driver of the transporter drives slowly, but once you get the knack of it, it is possible to do this stunt at any speed where the ramps will stay solidly (in practice about 50-60 mph on a smooth road surface)
Right, so here is how: Get the driver of the transporter to drive on a relatively straight stretch of road, and make sure the road is clear. If they have to brake or swerve, this stunt can end nastily. Needless to say, this is to be done on closed circuits only. Make 100% sure that the ramps won't fall off - this could be disasterous.
The transporter is driving at speed, and the ramps are hanging off the back of the transporter. You, the stunt driver, will have to align your car, so the wheels will hit the ramps solidly. If you hit them half on and slide off sideways, you may be in trouble. In other words, being intimate with the size of your car etc is paramount.
when you are aligned with the transporter, sink back a few car lengths, and change gears so you are in your car's most efficient power band. With most smaller-engine cars, this will be from 2700 - 4000 rpm. if you have a turbo or supercharger, it will be higher. If you don't know what the best power band is for your car, you should stop reading this node here, and go do something useful. Like get used to your car.
When you are ready, you want to accelerate. It will basically be the inertia of your car that will carry you onto the ramps, so the speed difference between the transporter and you should be significant.
As you are closing on the ramps, you will want to make sure your alignment is correct. If you have a moment's doubt, hit the breaks and abort the run immediately.
Now, you are driving 10-20 mph faster than the trailer, as you approach the ramps. Just before you hit the ramp, you will want to press your clutch all the way in. This is because if you fail to do so, your gearbox will fall off: Bringing an engine from 5000 RPM to 0 RPM (your front wheels will stop as they hit the ramp) is very, very bad news for your engine and gearbox, and this is also the reason for why I am unsure how this stunt can be performed in an automatic transmission car.
Anyway, if you hit the clutch just before you hit the ramps, your inertia should still carry you safely onto the ramp - at least with your front wheels. Make sure to resist the temptation to hit the breaks, as your breaks will act on all 4 wheels of the car, including the ones still rolling at 50 mph on the road at the rear of the car. Hitting the breaks is likely to pull the car off the transporter, as you will basically be in a "battle" between your front breaks trying to hold the car on the trailer, and the rear wheels trying to pull the car off.
So here is the clever bit: When you are on the trailer with the front wheels, you will want to be in 2nd or even 1st gear. This means that you will want to change gears right when you first hit the clutch - at the same moment as you drive your front wheels onto the ramp.
One of two things will happen: Either, you will have had enough inertia to push the entire car onto the ramps, in which case you can leisurely engage the clutch again, and pull your car properly onto the transporter, or you will be holding your place on the ramps with your engine / gearbox, as your rear wheels are still rolling. In this case, if you have a front wheel drive car, just slowly pull the car forward (1st gear job), and your back wheels should disengage with the road eventually, and you can drive onto the transporter.
What about getting off the ramp again?
Far easier. Just initiate a backwards motion (use reverse, or have someone give the car a little shove), do NOT touch your brakes, and keep your clutch firmly depressed. Physics will take care of the rest: Your wheels will be jerked into speed, but that can't really harm. make sure your steering wheel is straightened, though, or you may be in for a nasty surprise. Put your car in the appropriate gear (top gear, most likely - or 3rd, if you are going slow), ease off the clutch, and hey presto!
What about other cars?
If you have a rear wheel drive car, you can in theory just slowly drive onto the ramp with your front wheels. (i.e the speed difference can be less). To get your rear wheels on the ramps, give it a jolt of full acceleration, and hit the clutch. When you feel the car go onto the ramps, apply the brakes, and you should be on the ramps. Shift gears, drive into the transporter at your leisure.
If you are driving a four-wheel drive car, you will be dependent of the whole car getting on the ramp in one go. On the other hand, many 4wd cars are quite heavy, and you may want to reconsider the whole project, as the ramps you are driving onto will be under some serious strain
So what about safety?
Safety-schmafety. Be careful, make sure your car has a rollcage fitted, and be a very, very good driver before you try this. In fact, don't try it at all, just use the knowledge to impress friends and possible sexual conquests at parties.